Parkland, about the three days surrounding JFK's death in Dallas, hits theaters on Oct. 4.

Efron plays Jim Carrico, the real-life doctor who was a 28-year-old first-year surgical resident when he became the first person to examine Kennedy at Parkland Memorial Hospital after the president was shot in Dealey Plaza.

"The three days are really shrouded in so much mystery and controversy with conspiracy theories," Efron said at TIFF. "Growing up, I didn't know what was fact or fiction. But the simple truths of what transpired that we know for a fact are all in this movie."

We'll see even more of Efron in January with the release of That Awkward Moment, a comedy also starring Miles Teller and Michael B. Jordan about a group of young guys who vow to stay single.